code: def get_ghstack_token():
      pattern = "github_oauth = (.*)"
      with open(expanduser("~/.ghstackrc"), "r+") as f:
          config = f.read()
      matches = re.findall(pattern, config)
      if len(matches) == 0:
          raise RuntimeError("Can't find a github oauth token")
      return matches[0]
  
file_path: audio/tools/release_notes/retrieve_prs.py
imports: import argparse
  import json
  import re
  import subprocess
  from collections import namedtuple
  from os.path import expanduser
  import requests
label_desc: Use image node_id 4 for calling a global function with example usage: get_ghstack_token() and returns: matches